Patent GB-190507173-A (GB)
Title: Improvements in or relating to Apparatus for Advertising and like purposes.
Inventor: LEATHER WILLIAM GEORGE
Filed: 1905-04-05
Granted: 1905-10-19
Abstract: 7173. Leather, W. G. April 5. Magic - lantren apparatus.-Relates to apparatus for advertising and similar purposes, in which a series of signs is projected on a screen, the apparatus being electrically-operated and controlled by clock-work. A wheel or drum B, Fig. 1, carries a number of frames G, which are hollow or transparent at their centres and ate made with side grooves C<1>, stops C<2>, and springs C3, as shown, for the purpose of holding the slides to be exhibited by means of the lantern D. The operation of changing the sign exhibited. is as follows:-On the circuit of the electro-magnet H being closed, ;the core H' is pulled down against the action of the spring J, and the end F of the lever F,F' is raised. The link L thus lifts the catch K free of the projection E with which it engages, and the wheel B is unlocked. A pin in the cam-slot L<3> moves the link L so that its slot L<1> is freed from the projection K<3>, and the catch K falls upon the next projection E. The pawl G, which has a movement round its pivot G<1> limited by its extensions G<3> and a stop G', comes in contact with a projection E, and rotates the wheel until the wheel is again locked by the projection E on which the catch K rests coming in contact with the extension K<2>. On the electromagnet circuit being opened, the spring J. reverses the motion of the lever F, F<1>, the pawl. G passes the projection in its path, and the link L is directed by its cam-guide to bring its bevelled part. L<2> into contact with the projection K<3>, after which . the slot L<1> re-engages with the projection K<3>, a . spring L<4> being attached to the link L and to the fixed support A' to ensure this re-engagement. The making and. breaking of the electro-magnet circuit is affected by any convenient clock-operated switch which will effect the changes sufficiently quickly. The apparatus may be started and stopped by clock-work, and, in this case, the switches shown in Figs. 2 and 3 may be used, Fig. 2 showing a switch designed for giving a. sharp contact, and Fig. 3 a switch designed to, give a sharp cut-off. The upper part of each switch is on one circuit, say the lantern circuit, while the lower part of each is on the electro-magnet circuit, which also contains the rapidly-operated switch mentioned above. The switches are provided with fixed contacts N, P and spring contacts N<1>, P<1>, the springs N<2> tending to make contact and the strings P<2> tending to break contact. The contacts are fixed to insulating blocks R, and the two movable parts shown in each Figure are held together by an insulating block Q. The contacts are made and broken by the slowly-moving cams 0, 0', which move the extensions N<3>, P<3>. The portions of the cams shown, by dotted lines are detachable, so that the times of. starting and stopping the apparatus may be varied. The clockoperated switch in the electro-magnet circuit may conveniently be similar to that show in Fig. 2, but operated by. a cam attached to the seconds' arbor of the clock, the cam being circular with depressions in its periphery equal in number to the number of signs shown per minute. '